//
//  AppDelegate.swift
//  MyBlog
//
//  Created by lvtienan on 15/7/28.
//  Copyright © 2015年 ltn. All rights reserved.
//

import UIKit

// 在类的外边写的常量或者变量就是全局能够访问的
// 视图控制器能够切换的通知字符串
let HMRootViewControllerSwitchNotification = "HMRootViewControllerSwitchNotification"

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?


    func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
        
        // 注册通知
        NSNotificationCenter.defaultCenter().addObserver(self, selector: "switchViewController:", name: HMRootViewControllerSwitchNotification, object: nil)
        
        window = UIWindow(frame: UIScreen.mainScreen().bounds)
        
        window?.backgroundColor = UIColor.whiteColor()
        
       // window?.rootViewController = MainTabBarController()
        window?.rootViewController = defaultViewController()
        
        window?.makeKeyAndVisible()
        
        setupAppearance()
        
        
        return true
    }
    
    // APPdelegate 只有程序被销毁之后才会执行
    deinit {
        // 注销通知
        NSNotificationCenter.defaultCenter().removeObserver(self)
    }
    
    // 切换控制器
    func switchViewController(n:NSNotification) {
        let mainVC = n.object as! Bool
        window?.rootViewController = mainVC ? MainTabBarController () : WelcomeViewController()
            
    }
    
    // 返回启动默认的控制器
    private func defaultViewController() -> UIViewController {
        // 1. 如果用户没有登录,返回主控制器
        if !UserAccount.userLogin {
            return MainTabBarController()
        }
        
        // 2. 登录,判断是否是新版本.如果是返回新特性,否则返回欢迎
       return isNewUpdate() ? NewFeatureViewController() : WelcomeViewController()
    }
    
    /// 检查是否有新版本
    private func isNewUpdate() -> Bool {
        // 1. 获取当前程序的版本
        
       let currentVersion = Double (NSBundle.mainBundle().infoDictionary!["CFBundleShortVersionString"] as! String)!
        
        // 2. 获取程序之前的版本
        let sandboxVersionKey = "sandboxVersionKey"
        let sandboxVersion = NSUserDefaults.standardUserDefaults().doubleForKey(sandboxVersionKey)
        
        // 3. 将当前的版本保存到偏好设置
        NSUserDefaults.standardUserDefaults().setDouble(currentVersion, forKey: sandboxVersionKey)
        
        // 4. 返回比较结果
        
        return currentVersion > sandboxVersion
    }
    
    /**
    设置外观
    */
    private func setupAppearance() {
         UINavigationBar.appearance().tintColor = UIColor.orangeColor()
        // 这里 tintColor 就是选中之后的颜色
        //tabBar.tintColor = UIColor.orangeColor()
        UITabBar.appearance().tintColor = UIColor.orangeColor()
        
    }

    func applicationWillResignActive(application: UIApplication) {
        // Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
        // Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.
    }

    func applicationDidEnterBackground(application: UIApplication) {
        // Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
        // If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
    }

    func applicationWillEnterForeground(application: UIApplication) {
        // Called as part of the transition from the background to the inactive state; here you can undo many of the changes made on entering the background.
    }

    func applicationDidBecomeActive(application: UIApplication) {
        // Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
    }

    func applicationWillTerminate(application: UIApplication) {
        // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
    }


}

